Onetime UFC title challenger Shane Carwin (12-2 MMA, 4-2 UFC) will have to wait a little longer to return to the win column.

The injury bug has struck yet again, and an ailing back has forced Carwin to go under the knife and remain on the sidelines until spring or summer of 2012.

Carwin announced his condition on his official website, Shane-Carwin.com.

"I have spent my entire fighting career dealing with injuries from my football career," Carwin wrote. "I have done my best to get through my training, and I have been blessed to get through my fights with relatively little to no damage.

"As I ramped up my training for UFC 141, my body locked up during training. It wasn't like the (Brock) Lesnar fight, but my back just tightened up and I froze. I scheduled an MRI, and the results showed that my disc in my lower back is into the nerves. My doctor gave me two options: retire and I could probably go on for a few years without surgery or I could undergo surgery and continue my career.

"The decision was easy. I have unfinished business. The UFC had me lined up to face one of the best in the world and I am confident I have everything I need to be a champion. I am scheduling surgery and I hope to return to the octagon by spring or summer 2012."

"The decision was easy. I have unfinished business. The UFC had me lined up to face one of the best in the world and I am confident I have everything I need to be a champion. I am scheduling surgery and I hope to return to the octagon by spring or summer 2012."

"The decision was easy. I have unfinished business. The UFC had me lined up to face one of the best in the world and I am confident I have everything I need to be a champion. I am scheduling surgery and I hope to return to the octagon by spring or summer 2012."

"The decision was easy. I have unfinished business. The UFC had me lined up to face one of the best in the world and I am confident I have everything I need to be a champion. I am scheduling surgery and I hope to return to the octagon by spring or summer 2012."

Wonder who they had him lined up against.

Good question. Maybe they were going to have him face Werdum.

I wouldn't mind that fight, and you're probably right. Can't think of anyone else inside the UFC I would consider "one of the best in the world" that isn't already lined up.